The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.
Video and audio calls and conferences are becoming both more common and larger in size every day. Originally, video calls, audio calls, and conferences hosted using computers were limited to direct connections between users in which a first user called a second user, enabling the users to see and hear each other during the call. As methods improved, conferences of five, ten, or more users all with streaming video and audio became more common. Simply sending all video and audio data from each participant to every other participant in such a large conference often is not feasible due to limitations on network bandwidth in local area networks and internetworks and the limited processing power in some client computing devices.
In response, solutions to large video and audio conferences were implemented with media servers using two general approaches: multipoint control units (MCU) and selective forwarding units (SFU). MCUs receive and process audio and video data from clients and typically mix the audio and video to create a single composite video. The composite video is then streamed to the clients in a single mix. While this solution enables relatively simple client software, the processing power needed for the MCU is high, and the resulting presentation at the client is generally inflexible. SFUs, in contrast, are more similar to packet data routers, as SFUs forward packets without media processing.
Another, or additional, solution is to use multiple media servers for a single video or audio conference, thereby sharing the computing workload. However, using multiple media servers for a single video or audio conference may result in inefficient use of bandwidth. Improvements for conferences using multiple media servers are needed.